I. Field of the Invention
The present invention provides a method for removing incipient carious lesions and/or stain from teeth and, more particularly, from human teeth.
II. Description of the Prior Art
Carious lesions or tooth decay are initiated by bacteria which reside in tooth plaque. These bacteria produce acids which diffuse through a matrix of water-protein-lipid and ultimately dissolve the hydroxyapatite crystals which form the tooth enamel.
The dissolution of the enamel hydroxyapatite crystals by the bacteria acid is an intermittent and relatively slow process often extending up to a period of three years before the lesion can be diagnosed clinically by either X-rays or clinical examination. At this point, the carious lesion has invaded the tooth dentin and requires restoration. Such restoration is typically accomplished by drilling and filling the tooth.
Incipient carious lesions are areas of the tooth where the decay can be seen but has not yet broken through the enamel and invaded the dentin. There is no previously known method for removing such incipient decay and/or stain on the enamel surfaces of the tooth although good oral hygiene techniques, such as brushing, and tooth coating slow the tooth decay process. However, once incipient decay is visible on the tooth, the decay will eventually penetrate through the enamel and into the dentin whereupon restoration of the tooth is required.
There have been a number of previously known experiments in which teeth have been subjected to laser irradiation to determine the alteration, if any, of the physical and/or chemical properties of the dental enamel. These studies have shown that the hydroxyapatite crystals that form the enamel fuse somewhat at the surface when lased and renders the enamel more impervious to acids of the type which cause tooth decay. These previous studies, however, have also concluded that the use of a laser to remove tooth decay is ineffective due, in part, to possible damage to the pulp. None of these previously known studies, however, have employed a laser in an attempt to remove incipient carious lesions from the tooth.